Controlling the Speed of Light-Activated Colloids with a Constant, Uniform Magnetic Field

Brad Landry, Victoria Girgis, John G. Gibbs

Research output: Contribution to journalArticlepeer-review

6 Scopus citations


It is demonstrated how the strength of activation for photocatalytic, self-propelled colloids can be enhanced with a constant, uniform magnetic field. When exposed to ultraviolet light and hydrogen peroxide, the titanium dioxide-based colloids become actively propelled. Due to the iron oxide core, a uniform field oriented perpendicular to the surface where motion takes place causes the asymmetrically shaped particles to rotate, which consequently leads to an increase in activity. The field-dependent dynamics of self-propulsion is quantified, and a qualitative description of how this effect arises is proposed. Since the application of the field is easily reversible, modulating the field on-and-off serves as a de facto “switch” that controls particle behavior.

Original languageEnglish (US)
Article number2003375
Issue number35
StatePublished - Sep 1 2020


  • anisotropic colloids
  • light-activated colloids
  • magnetic-field speed modulation
  • speed control
  • titanium dioxide

ASJC Scopus subject areas

  • Biotechnology
  • Biomaterials
  • General Chemistry
  • General Materials Science


Dive into the research topics of 'Controlling the Speed of Light-Activated Colloids with a Constant, Uniform Magnetic Field'. Together they form a unique fingerprint.

Cite this